Caller ID on Headset

I’m helping my mom with caller Id landline issue. Caller ID works on the TV. If the TV is on and the phone rings the callers name is displayed. The issue she is having is with her Panaonic KX-TGF570 telephone answering machine with 4 handsets. She prefers to use this answering machine to the service offered by Xfinity. The issue is that the handsets are no longer displaying the caller ID. This feature was working on the headsets up until 12/19. For some reason after that it stopped. She doesn’t want to have the TV on all the time to just see who is calling. I have made sure the Panaonic headsets all have Caller ID set to yes but it still doesn’t display who is calling. It makes no sense that it would be working on the headsets and then stop. Anyone having this issue and if so, found a solution?